[Modern viewpoints of hip joint dysplasia, clinical and radiologic. III. Radiologic follow-up]

Area of Science:

• Pediatric Orthopedics
• Radiology
• Developmental Biology

Background:

• Developmental dysplasia of the hip (DDH) is a condition that can be identified early in infancy.
• Delayed diagnosis can lead to complications and less effective treatment.
• Current diagnostic methods may not be sensitive enough for early, mild cases.

Purpose of the Study:

• To establish the earliest age for unequivocal diagnosis of hip dysplasia.
• To identify key radiographic signs indicative of hip dysplasia in infants.
• To evaluate the effectiveness of current diagnostic standards and treatment timelines.

Main Methods:

• Clinical and radiological observations of infants within the first 3 months of life.
• Analysis of specific radiographic features, including acetabular angle, ossification, and roof contour.
• Comparison of diagnostic findings with established statistical measures (Tonnis statistics).

Main Results:

• Hip dysplasia can be reliably diagnosed as early as 7 weeks of age.
• Essential radiographic signs include wedge-segments, delayed ossification, "Tailliation," subchondral sclerosis, double contour, and steep PDW in severe cases.
• Standard statistical measures are insufficient for early diagnosis; focus on structural acetabular roof changes is necessary.
• Mild dysplasias are often missed by PDW (proximal distal width) and require detailed assessment of acetabular roof morphology.

Conclusions:

• Early diagnosis of hip dysplasia is possible within the first 3 months of life, with definitive signs appearing by 7 weeks.
• Treatment for hip dysplasia should be initiated before 7 weeks of age, even if PDW appears normal.
• The dysplastic acetabulum is a pathological entity, not merely an immature one, necessitating targeted radiographic evaluation of the acetabular roof.